Cultivation of kelp has been well established throughout Asia, and there is now growing interest in the cultivation of macroalgae in Europe to meet future resource needs. If this industry is to ...become established throughout Europe, then balancing the associated environmental risks with potential benefits will be necessary to ensure the carrying capacity of the receiving environments are not exceeded and conservation objects are not undermined. This is a systematic review of the ecosystem changes likely to be associated with a developing seaweed aquaculture industry. Monitoring recommendations are made by risk ranking environmental changes, highlighting the current knowledge gaps and providing research priorities to address them. Environmental changes of greatest concern were identified to include: facilitation of disease, alteration of population genetics and wider alterations to the local physiochemical environment. Current high levels of uncertainty surrounding the true extent of some environmental changes mean conservative risk rankings are given. Recommended monitoring options are discussed that aim to address uncertainty and facilitate informed decision-making. Whilst current small-scale cultivation projects are considered ‘low risk’, an expansion of the industry that includes ‘large-scale’ cultivation will necessitate a more complete understanding of the scale dependent changes in order to balance environmental risks with the benefits that seaweed cultivation projects can offer.
Despite a long history of rearing Atlantic salmon in hatcheries in Norway, knowledge of molecular and physiological aspects of juvenile development is still limited. To facilitate introduction of ...alternative feed ingredients and feed additives during early phases, increased knowledge regarding the ontogeny of the digestive apparatus in salmon is needed. In this study, we characterized the development of the gastrointestinal tract and accessory digestive organs for five months following hatch by using histological, biochemical and molecular methods. Furthermore, the effects of a diet containing 16.7% soybean meal (SBM) introduced at start-feeding were investigated, as compared to a fishmeal based control diet. Salmon yolk sac alevins and fry were sampled at 18 time points from hatch until 144 days post hatch (dph). Histomorphological development was investigated at 7, 27, 46, 54 and 144 dph. Ontogenetic expression patterns of genes encoding key digestive enzymes, nutrient transporters, gastrointestinal peptide hormones and T-cell markers were analyzed from 13 time points by qPCR. At 7 dph, the digestive system of Atlantic salmon alevins was morphologically distinct with an early stomach, liver, pancreas, anterior and posterior intestine. About one week before the yolk sac was internalized and exogenous feeding was started, gastric glands and developing pyloric caeca were observed, which coincided with an increase in gene expression of gastric and pancreatic enzymes and nutrient transporters. Thus, the observed organs seemed ready to digest external feed well before the yolk sac was absorbed into the abdominal cavity. In contrast to post-smolt Atlantic salmon, inclusion of SBM did not induce intestinal inflammation in the juveniles. This indicates that SBM can be used in compound feeds for salmon fry from start-feeding to at least 144 dph and/or 4-5 g body weight.
Global population growth and changing diets increase the importance, and challenges, of reducing the environmental impacts of food production. Farmed seafood is a relatively efficient way to produce ...protein and has already overtaken wild fisheries. The use of protein-rich food crops, such as soy, instead of fishmeal in aquaculture feed diverts these important protein sources away from direct human consumption and creates new environmental challenges. Single cell proteins (SCPs), including bacteria and yeast, have recently emerged as replacements for plant-based proteins in salmon feeds. Attributional life cycle assessment is used to compare salmon feeds based on protein from soy, methanotrophic bacteria, and yeast ingredients. All ingredients are modeled at the industrial production scale and compared based on seven resource use and emissions indicators. Yeast protein concentrate showed drastically lower impacts in all categories compared to soy protein concentrate. Bacteria meal also had lower impacts than soy protein concentrate for five of the seven indicators. When these target meals were incorporated into complete feeds the relative trends remain fairly constant, but benefits of the novel ingredients are dampened by high impacts from the nontarget ingredients. Particularly, primary production requirements (PPR) are about equal and constant across all feeds for both analyses since PPR was driven by fishmeal and oil. The bacteria-based feed has the highest climate change impacts due to the use of methane to feed the bacteria who then release carbon dioxide. Overall, the results of this study suggest that incorporating SCP ingredients into salmon feeds can help reduce the environmental impacts of salmon production. Continued improvements in SCP production would further increase the sustainability of salmon farming.
In this study, Candida utilis was included as alternative protein source in diets for Atlantic salmon (Salmo salar) parr and the effects on growth performance and distal intestinal (DI) health were ...assessed. The potential of C. utilis to counteract possible adverse effects of a high soybean meal (SBM) diet was additionally assessed by using graded levels of C. utilis in combination with a 40% SBM diet. Six experimental diets were formulated: Fishmeal control (FM); FM with 20% C. utilis (FM20CU); SBM-based diet containing 40% SBM (SBM); three SBM-based test diets, where wheat gluten and starch were substituted with increasing levels of C. utilis of 5%, 10% and 20% (SBM5CU, SBM10CU and SMB20CU, respectively). A total of 2700 Atlantic salmon parr with an average weight of 4.4 g were distributed into 18 tanks and the diets were fed in triplicates. The experiment lasted 28 days and sampling for histology and gene expression analysis was done at the end of the experiment.
The fish grew to an average weight of 14.8 g in 28 days. Fish fed FM20CU obtained a significantly higher specific growth rate (SGR) of 4.59 than the other dietary groups. While fish fed FM and FM20CU displayed normal morphology of the DI, fish fed SBM-based diets showed mild histological changes in the DI that can be related to classical SBM induced enteritis (SBMIE). These changes included reduced height of simple folds and decreased presence of supranuclear vacuoles. The severity of these changes was not altered with increasing levels of C. utilis in the SBM diet. The expression of four of the five selected genes analyzed in the DI were altered by 40% dietary SBM inclusion. Aquaporin 8ab demonstrated the clearest changes among dietary groups, showing down-regulation independent of dietary inclusion of C. utilis. The strong down-regulation of aquaporin has been observed before and may be an indicator for intestinal barrier dysfunction. In conclusion, adding C. utilis to diets for Atlantic salmon parr gave high growth performance without any obvious adverse effects on intestinal health, but were unable to counteract the mild histology changes seen in DI of the SBM fed fish.
•Dietary Candida utilis yeast gave high growth performance and normal intestinal health in Atlantic salmon parr.•Intestinal histology and gene expression in salmon parr fed high soybean meal diets were similar to that of saltwater adapted salmon.•Dietary inclusion of C. utilis did not support normal morphology in distal intestine when combined with 40% soybean meal.
Plant products in general and soybeans in particular can challenge the function and health of the intestinal tract. Salmonids develop an intestinal inflammation when fed diets containing soybean meal ...(SBM) and certain other legume ingredients. In the present study a 44K oligonucleotide salmonid microarray, qPCR and histology were used to investigate early response mechanisms in the distal intestine of Atlantic salmon (Salmo salar L.) during the first week of oral exposure to a diet containing 20% extracted SBM. The distal intestine transcriptome was profiled on days 1, 2, 3, 5 and 7 and compared to a control group fed fishmeal as the sole protein source. Histological evaluation of the distal intestine revealed the first signs of inflammation on day 5. The most prominent gene expression changes were seen on days 3 and 5. Up-regulation in immune-related genes was observed during the first 5 days, including GTPase IMAP family members, NF-kB-related genes and regulators of T cell and B cell function. Many functional genes involved in lipid metabolism, proteolysis, transport, metabolism and detoxification were initially up-regulated on days 1–3, possibly as an attempt by the tissue to compensate for the initiating immune response. Cell repair and extracellular matrix remodeling genes were up-regulated (heparanase, collagenase) on days 3 and 5. Down regulation of genes related to endocytosis, exocytosis, detoxification, transporters and metabolic processes from day 5 indicated initiation of dysfunction of digestive and metabolic functions that may occur as a result of inflammation or as a response to the introduction of soybean meal in the diet. This is the first study conducting transcriptomic profiling to characterize early responses during the development of SBMIE. Switching Atlantic salmon from a fishmeal to a 20% SBM diet resulted in rapid changes to the intestinal transcriptome, indicating an immune reaction with subsequent impaired epithelial barrier function and other vital intestinal functions.
► Soybean meal diet induced changes in gene expression from the first day of feeding. ► Major changes in gene expression occurred on days 3 and 5 of soybean meal feeding. ► Most changes were related to immune response and epithelial barrier integrity.
Yeast produced from lignocellulosic biomass has the potential to serve as a high-quality protein source with health benefits, especially during critical stages of the Atlantic salmon life cycle, such ...as during seawater transfer (SWT). In this study, we evaluated the effect of adding 25% Candida utilis yeast to salmon feed on growth performance and overall health by using morphometry, immunohistochemistry, cytokine enzyme-linked immunosorbent assays (ELISA) and gene expression analysis during and after SWT. There were four dietary treatments: 1) control diet in freshwater (FW) and seawater (SW) (Control); 2) control diet in FW and a yeast-based diet in SW (Control/Yeast); 3) yeast-based diet in FW and SW (Yeast); 4) yeast-based diet in FW and a control diet in SW (Yeast/Control). Our results showed that fish fed the yeast diet throughout the FW and SW period achieved higher feed intake and higher growth rate than fish fed the control diet. Morphometric and immunochemical analyses of the distal intestine (DI) revealed decreased length and number of CD3 labeled cells in the simple folds of fish fed control diet, while no changes were observed in fish fed the yeast diet. Furthermore, yeast significantly decreased the secretion of IFNγ, TNFα, IL-1β, IL-8, and modulated the gene expression of aquaporin 8 (aqp8ab), superoxide dismutase (sod1) and major histocompatibility complex 1 (mhc1) in DI, suggesting reduced inflammatory processes in yeast fed fish. These findings indicate that Candida utilis yeast is a promising alternative protein source with functional properties in diets for smolting Atlantic salmon before and after SWT.
•Yeast successfully modified immunosuppressive responses and histological parameters related to seawater acclimation.•Yeast decreased secretion of cytokines in distal intestine as well as decreased the expression of its genes.•Fish fed yeast had better growth performance and feeding behaviour in fresh- and post seawater transfer.
Antinutritional factors (ANFs) can disrupt digestive and other intestinal functions. ANFs in soybean meal (SBM) are implicated in proliferative and inflammatory responses in the intestine of various ...(functionally) monogastric animals, including Atlantic salmon (Salmo salar L.). The goal of the current study was to investigate the effect of ex vivo exposure of mid and distal intestinal tissue of salmon to soybean saponins (SAP), lectin (LEC) and Kunitz' trypsin inhibitor (KTI), singly and in combination, on epithelial function, as assessed by measuring in vitro glucose uptake pathways along a glucose concentration gradient. As solubilization of SAP in the calcium-containing Ringer's solution was problematic but resolved with the addition of a physiological concentration of bile collected from the gall bladder of salmon, an evaluation of bile effects became an added element. Results indicated that bile increased baseline glucose absorption and possibly transport, and also had a protective effect on the epithelial barrier, at least partially due to taurocholate. Compared to controls, tissues exposed to LEC+bile, KTI+bile and LEC+KTI+bile exhibited increased glucose uptake at the higher glucose concentrations, apparently due to markedly increased tissue permeability. Addition of SAP, however, attenuated the response, possibly by binding bile components. SAP+bile, also in combination with LEC and/or KTI, as well as LEC, KTI and LEC+KTI without bile often reduced transcellular glucose uptake pathways, while maintaining low tissue permeability. SAP+LEC+KTI+bile, LEC and KTI caused the most marked reductions. The distal intestine was more affected, reflecting the restriction of in vivo SBM-induced inflammatory changes to this region.
The setation of the mouthparts, gut contents and video recordings of live individuals of the deep-sea clawed lobsters (Nephropidae)
Metanephrops formosanus,
M. armatus and the spiny lobster ...(Palinuridae)
Puerulus angulatus from northwest Pacific waters were analysed to get an insight into their feeding modes. A comparison of SEM photos shows a high degree of similarity between the morphology and setation of the mouthparts of
M. formosanus and
M. armatus, but that of
P. angulatus was very different to
Metanephrops. Serrate setae are most abundant on the feeding appendages of
M. formosanus and
M. armatus. The mouthparts of
P. angulatus are dominated by simple and cuspidate setae. Gut contents of
Metanephrops spp. contained small crustacean parts, fish and bivalves and a considerable amount of sediment (∼60% relative abundance). Guts of
Puerulus contained mostly small pieces of fish and crustaceans and only a relatively minor amount of sediment (<10%). Video analysis revealed that the studied
Metanephrops species are able to handle soft food items by cutting and abrading movements of the mouthparts.
Puerulus would not feed on presented food items under lab conditions. The feeding appendages and their setation are clearly related to the feeding modes of the species studied. Both
Metanephrops species have slender appendages with fine and sharp setae, suggesting it is a predator and/or scavenger on small crustaceans and ingest deposits to a limited extent.
Puerulus angulatus has thick and shorter appendages with strong simple and cuspidate setae, possibly corresponding to a more predatory lifestyle.
•The CRISP registry collects representative, nationwide data on NSCLC in Germany.•CRISP mirrors the treatment and disease trajectory of patients with advanced NSCLC.•Biomarker testing rates increased ...over time, yet are still improvable.•17.7 % of the patients presented with a druggable alteration.•Median PFS was longer for patients with a druggable EGFR or ALK alteration.
An increasing number of treatment-determining biomarkers has been identified in non-small cell lung cancer (NSCLC) and molecular testing is recommended to enable optimal individualized treatment. However, data on implementation of these recommendations in the “real-world” setting are scarce. This study presents comprehensive details on the frequency, methodology and results of biomarker testing of advanced NSCLC in Germany.
This analysis included 3,717 patients with advanced NSCLC (2,921 non-squamous; 796 squamous), recruited into the CRISP registry at start of systemic therapy by 150 German sites between December 2015 and June 2019. Evaluated were the molecular biomarkers EGFR, ALK, ROS1, BRAF, KRAS, MET, TP53, RET, HER2, as well as expression of PD-L1.
In total, 90.5 % of the patients were tested for biomarkers. Testing rates were 92.2 % (non-squamous), 70.7 % (squamous) and increased from 83.2 % in 2015/16 to 94.2% in 2019. Overall testing rates for EGFR, ALK, ROS1, and BRAF were 72.5 %, 74.5 %, 66.1 %, and 53.0 %, respectively (non-squamous). Testing rates for PD-L1 expression were 64.5 % (non-squamous), and 58.5 % (squamous). The most common testing methods were immunohistochemistry (68.5 % non-squamous, 58.3 % squamous), and next-generation sequencing (38.7 % non-squamous, 14.4 % squamous). Reasons for not testing were insufficient tumor material or lack of guideline recommendations (squamous). No alteration was found in 37.8 % (non-squamous), and 57.9 % (squamous), respectively. Most common alterations in non-squamous tumors (all patients/all patients tested for the respective biomarker): KRAS (17.3 %/39.2 %), TP53 (14.1 %/51.4 %), and EGFR (11.0 %/15.1 %); in squamous tumors: TP53 (7.0 %/69.1 %), MET (1.5 %/11.1 %), and EGFR (1.1 %/4.4 %). Median PFS (non-squamous) was 8.7 months (95 % CI 7.4–10.4) with druggable EGFR mutation, and 8.0 months (95 % CI 3.9–9.2) with druggable ALK alterations.
Testing rates in Germany are high nationwide and acceptable in international comparison, but still leave out a significant portion of patients, who could potentially benefit. Thus, specific measures are needed to increase implementation.